The invention concerns a continuous-operation centrifuge drum for concentrating suspended solids, wherein the concentrated solids are diverted out of an outer solids space through channels into an inner chamber, whence the concentrated solids are continuously extracted, whereby at least one vortical-outflow space is positioned between the channels and the inner chamber, with the points at which the medium enters the channels distributed around the outer demarcation of the outflow space and with the outlet from the outflow space extending from a radially outward region in the outflow space to the inner chamber.
A centrifuge drum of this type is already known from German Patent 3 513 335. The channels open into a vortical-outflow space that is concentric with the axis of rotation. The solids enter the outflow space at a peripheral speed that varies as the result of friction as they flow through the space to an extent that depends on their viscosity. The viscosity-dependent change in the peripheral speed leads to alteration in the output of solids, to the extent that the output of extracted solids is automatically regulated within certain limits.
To attain the aforesaid effect, however, it may be necessary to lengthen the radius of the vortical-outflow spaces, which is very expensive.